1. Field of the Invention
The present invention relates to compositions for forming golf balls and to multi-piece golf balls.
2. Description of the Related Art
In the prior art, ionomer resins have been regarded as a standard among materials for the cover of multi-piece golf balls. A golf ball having a cover formed of an ionomer resin exhibits a long carry distance and high durability, however such a golf ball gives a hard feel when hit, and tends to show poor control ability because of the quick ball release when hit.
In recent years, soft covers made of polyurethane resin or the like have been frequently employed to provide a soft feel when hit and to improve the control ability.
The properties required in golf balls include, in combination, a soft feel and good control ability as well as a long carry distance. When soft materials are used for the cover of a golf ball, a soft feel is gained but a long carry distance is not to be expected. On the other hand, when a hard material is used for the cover, a long carry distance is achievable, but a soft feel can not be obtained. It is difficult to realize a golf ball which satisfies all these conflicting properties.
Concerning techniques for achieving such an object, Japanese Unexamined Patent Publication No. 2003-49028 (claim 1, Paragraph 0008 and elsewhere) discloses the formation of a cover of a multi-piece golf ball using a composition containing an organic or inorganic basic compound as a dispersant to be used while adding a polyurethane elastomer to an ionomer resin.